samedi 11 janvier 2020

NASA Animates World Path of Smoke and Aerosols from Australian Fires

NOAA & NASA - Suomi NPP Mission patch.

Jan. 11, 2020

A fleet of NASA satellites working together has been analyzing the aerosols and smoke from the massive fires burning in Australia.

Animation above: VIIIRS Red-Green-Blue imagery provides a “true-color” view of the smoke. (Note that these images do not represent what a human would see from orbit. In these images, the effect of Rayleigh scattering, which would add “blue haze,” has been taken out.) While useful, it is often hard to distinguish smoke over clouds and, sometimes, over dark ocean surfaces. Animation Credits: NASA/Colin Seftor.

The fires in Australia are not just causing devastation locally. The unprecedented conditions that include searing heat combined with historic dryness, have led to the formation of an unusually large number of pyrocumulonimbus (pyrCbs) events. PyroCbs are essentially fire-induced thunderstorms. They are triggered by the uplift of ash, smoke, and burning material via super-heated updrafts. As these materials cool, clouds are formed that behave like traditional thunderstorms but without the accompanying precipitation.

PyroCb events provide a pathway for smoke to reach the stratosphere more than 10 miles (16 km) in altitude. Once in the stratosphere, the smoke can travel thousands of miles from its source, affecting atmospheric conditions globally. The effects of those events -- whether the smoke provides a net atmospheric cooling or warming, what happens to underlying clouds, etc.) -- is currently the subject of intense study.

Suomi NPP (National Polar-orbiting Partnership). Image Credits: NOAA/NASA

NASA is tracking the movement of smoke from the Australian fires lofted, via pyroCbs events, more than 9.3 miles (15 kilometers) high. The smoke is having a dramatic impact on New Zealand, causing severe air quality issues across the county and visibly darkening mountaintop snow.

Two instruments aboard NASA-NOAA’s Suomi National Polar-orbiting Partnership (NPP) satellite -- VIIRS and OMPS-NM -- provide unique information to characterize and track this smoke cloud. The VIIRS instruments provided a “true-color” view of the smoke with visible imagery. The OMPS series of instruments comprise the next generation of back-scattered UltraViolet (BUV) radiation sensors. OMPS-NM provides unique detection capabilities in cloudy conditions (very common in the South Pacific) that VIIRS does not, so together both instruments track the event globally.

Animation above: The UV aerosol index is a qualitative product that can easily detect smoke (and dust) over all types of land surfaces. It also has characteristic that is particularly well suited for identifying and tracking smoke from pyroCb events: the higher the smoke plume, the larger the aerosol index value. Values over 10 are often associated with such events. The aerosol index values produced by some of the Australian pyroCb events have rivaled that larges ever recorded. Animation Credits: NASA/Colin Seftor.

At NASA Goddard, satellite data from the OMPS-NM instrument is used to create an ultraviolet aerosol index to track the aerosols and smoke. The UV index is a qualitative product that can easily detect smoke (and dust) over all types of land surfaces. To enhance and more easily identify the smoke and aerosols, scientists combine the UV aerosol index with RGB information.

Map of Australia's fire activity. Image Credit: NASA

Colin Seftor, research scientist at Goddard said, “The UV index has a characteristic that is particularly well suited for identifying and tracking smoke from pyroCb events: the higher the smoke plume, the larger the aerosol index value. Values over 10 are often associated with such events. The aerosol index values produced by some of the Australian pyroCb events have rivaled that largest values ever recorded.”

Beyond New Zealand, by Jan. 8, the smoke had travelled halfway around Earth, crossing South America, turning the skies hazy and causing colorful sunrises and sunsets.

The smoke is expected to make at least one full circuit around the globe, returning once again to the skies over Australia.

Animation above: Combining UV aerosol index with RGB information is one way to enhance both. Image Credits: NASA/Colin Seftor.

NASA’s satellite instruments are often the first to detect wildfires burning in remote regions, and the locations of new fires are sent directly to land managers worldwide within hours of the satellite overpass. Together, NASA instruments detect actively burning fires, track the transport of smoke from fires, provide information for fire management, and map the extent of changes to ecosystems, based on the extent and severity of burn scars. NASA has a fleet of Earth-observing instruments, many of which contribute to our understanding of fire in the Earth system. Satellites in orbit around the poles provide observations of the entire planet several times per day, whereas satellites in a geostationary orbit provide coarse-resolution imagery of fires, smoke and clouds every five to 15 minutes.

For more information and imagery, visit NASA’s Fire/Smoke page:

NOAA & NASA Suomi NPP (National Polar-orbiting Partnership):

Animation (mentioned), Images (mentioned), Text, Credits: NASA/Lynn Jenner/Goddard Space Flight Center, by Colin Seftor/Rob Gutro.


vendredi 10 janvier 2020

Eye Checks, Pain Studies and Spacesuit Checks Wrap up Workweek

ISS - Expedition 61 Mission patch.

January 10, 2020

The Expedition 61 crew is continuing more research today into how the human body adapts to living in microgravity. U.S. spacesuits aboard the International Space Station are also being readied for the first of three spacewalks planned to start Jan. 15.

Eye checks were on the schedule Friday afternoon as astronauts Jessica Meir and Christina Koch took turns as Crew Medical Officer. The duo scanned the eyes of NASA Flight Engineer Andrew Morgan and Commander Luca Parmitano of ESA (European Space Agency) using an ultrasound device and optical coherence tomography gear.

Image above: NASA astronaut Christina Koch works on a U.S. spacesuit, with a patch of the Italian flag on the left shoulder, that Commander Luca Parmitano of ESA (European Space Agency) wore during a spacewalk on Dec. 2, 2019. Image Credit: NASA.

Morgan started the morning setting up a specialized mouse habitat that can create artificial gravity conditions aboard the orbiting lab. Mice physiology resembles that of humans, providing scientists fundamental insights into cellular and genetic alterations that occur in weightlessness.

Meir is getting the spacesuits ready she and Koch will wear on Jan. 15 and 20 for a pair of power maintenance spacewalks. She scrubbed cooling loops and filled water tanks before checking out suit hardware and checking for leaks. The spacewalking duo will replace older batteries with newer, more powerful batteries on the orbiting lab’s Port-6 truss structure.

Spacewalker in maintenance activity on ISS. Animation Credit: NASA

In the Russian segment of the space station, cosmonauts Alexander Skvortsov and Oleg Skripochka focused on life support maintenance and orbital plumbing tasks. Skvortsov also researched how microgravity affects pain sensation while Skripochka photographed the condition of space-exposed hardware.

Related links:

Expedition 61:


Mouse habitat:

Port-6 truss structure:

Pain sensation:

Space-exposed hardware:

Space Station Research and Technology:

International Space Station (ISS):

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.


Space Station Science Highlights: Week of January 6, 2020

ISS - Expedition 61 Mission patch.

Jan. 10, 2020

The week of Jan. 6, the crew of the International Space Station conducted scientific investigations including research on protein crystal growth, biofilm control and improving the intestinal microbiome of crew members. The crew packed samples from a number of studies into the SpaceX Dragon for return to Earth for analysis. Dragon departed the space station early the morning of Tuesday, Jan. 7, splashing down in the Pacific a few hours later.

Image above:  A waxing crescent Moon is pictured as the International Space Station orbited 260 miles above the north African country of Algeria. Image Credit: NASA.

Now in its 20th year of continuous human presence, the space station provides a platform for long-duration research in microgravity and for learning to live and work in space. Experience gained on the orbiting lab supports Artemis, NASA’s program to go forward to the Moon and on to Mars.

Here are details on some of the microgravity investigations currently taking place:

Improving crystal growth in space

Image above: NASA astronaut Jessica Meir works on the BioFabrication Facility (BFF), a 3-D biological printer that tests the printing of human organs and tissues in space away from the detrimental effects of Earth’s gravity. Image Credit: NASA.

The crew prepared crystals grown as part of the Effects of Impurities on Perfection of Protein Crystals, Partition Functions, and Growth Mechanisms (Advanced Nano Step) investigation for return to Earth. This Japan Aerospace Exploration Agency (JAXA) experiment monitors and records how specific impurities affect the development and quality of protein crystals. Detailed analysis of protein crystal structure contributes to research on production of targeted pharmaceuticals and therapies. More than 20 years of experiments have shown that microgravity produces higher quality protein crystals, but the improved success rate has been at most 60 percent. Advanced Nano Step aims to improve that rate, shorten the time needed for sample preparation, and find out what kinds of impurities reduce the quality of space-grown protein crystals.

Better control of biofilms

Animation above: NASA astronaut Christina Koch conducts operations for Space Biofilms. This investigation examines microbial species and their formation of biofilms, communities of microorganisms that attach to each other and to different surfaces. Animation Credit: NASA.

The crew also stowed Group Activation Packs (GAPs) from Space Biofilms into the Dragon capsule for return to Earth. This investigation examines microbial species and their formation of biofilms, or communities of microorganisms that attach to each other and to different surfaces. Biofilms can cause equipment malfunction and human illness and could present serious problems on future long-term space missions. Better control of biofilms could help better maintain crewed spacecraft and protect the health and safety of crew members as well as help prevent the introduction of Earth-based microbes to planetary bodies on which humans land.

A busy week for JAXA

Crew members conducted operations for several other JAXA investigations (JAXA) during the week, including Probiotics and Colloidal Clusters. Scientists are concerned that some harmful bacteria may grow stronger and more virulent in microgravity. At the same time, the human immune system becomes weaker in space, representing an increased risk to crew health. The Probiotics investigation studies whether beneficial bacteria (probiotics) improve the human intestinal microbiota and immune function on long-duration space missions. The crew collected saliva samples and completed questionnaires for the investigation.

JAXA’s Colloidal Clusters investigates the mechanism behind formation of clusters containing negatively and positively charged particles suspended in liquid. These clusters may be useful as building blocks for future photonic, or light-manipulating, materials. Crew members transferred investigation samples to the FROST facility in preparation for their eventual return to Earth for analysis. Two FROST units on the space station provide cold stowage to support experiments that require low temperatures and serve as additional cold storage for experiment samples such as plant cells, seeds and other materials.

Image above: Image from a burn conducted for the Confined Combustion investigation of flame spread in confined spaces, which may pose a more serious hazard than flame spread in open spaces. Image Credit: NASA.

Other investigations on which the crew performed work:

- The Confined Combustion investigation studies flame spread in confined spaces. Flame spread in such spaces, including buildings and vehicles, may pose a more serious hazard than it does in open spaces.

- Radi-N2, an investigation by the Canadian Space Agency (CSA), characterizes the neutron radiation environment on the space station to help define the risk to crew members and support development of advanced protective measures for future spaceflight.

- RR-19 examines the potential benefits of targeting the myostatin (MSTN) and activin signaling pathways to prevent skeletal muscle and bone loss during spaceflight.

- The Japan Aerospace Exploration Agency (JAXA) Space Moss investigation determines how microgravity affects mosses. Tiny plants without roots, mosses grow in a very small area, an advantage for their potential use on long space voyages.

- BioFabrication Facility (BFF) tests the printing of human organs and tissues in microgravity, a first step toward manufacturing entire human organs in space using refined biological 3D printing techniques.

- Biomolecule Extraction and Sequencing Technology (BEST) studies the use of DNA sequencing to identify microbial organisms and improve understanding of how humans, plants and microbes adapt to living in space.

- Food Acceptability examines changes in the appeal of food aboard the space station during long-duration missions. “Menu fatigue” from repeatedly consuming a limited choice of foods may contribute to the loss of body mass often experienced by crew members, potentially affecting astronaut health, especially as mission length increases.

- Vascular Echo examines changes in blood vessels and hearts of crew members in space and their recovery upon return to Earth. Some returning crew members have much stiffer arteries after space flight.

Space to Ground: Descending Dragon: 01/10/2020

Related links:

Expedition 61:

Advanced Nano Step:

Space Biofilms:


Colloidal Clusters:


ISS National Lab:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Michael Johnson/John Love, Lead Increment Scientist Expedition 61.

Best regards,

jeudi 9 janvier 2020

NASA’s Lucy Mission Confirms Discovery of Eurybates Satellite

NASA - LUCY Mission patch.

Jan. 9, 2020

NASA’s Lucy mission team is seeing double after discovering that Eurybates, the asteroid the spacecraft has targeted for flyby in 2027, has a small satellite. This “bonus” science exploration opportunity for the project was discovered using images taken by the Hubble Space Telescope’s Wide Field Camera 3 in September 2018, December 2019, and January 2020.

Image above: Illustration of NASA’s Lucy spacecraft, the first space mission to study Jupiter's Trojan asteroids — swarms of primitive bodies that are time capsules from the birth of our solar system. Image Credits: NASA/SwRI.

Launching in October 2021, Lucy will be the first space mission to study the Trojan asteroids, a population of small bodies orbiting the Sun “leading” and “trailing” Jupiter, at the same distance from the Sun as the gas giant. With flyby encounters past seven different asteroids – one in the Main Asteroid Belt and six in the Trojans, Lucy will be the first space mission in history to explore so many different destinations in independent orbits around our Sun.

“This newly discovered satellite is more than 6,000 times fainter than Eurybates, implying a diameter less than 1 km,” said Southwest Research Institute’s Hal Levison, principal investigator of the mission. “If this estimate proves to be correct, it will be among the smallest asteroids visited.”

Eurybates was first observed with Hubble in a search for small satellites in 2018, but it wasn’t until this past November when a Lucy team member noticed something in the data indicating a possible satellite.

“We asked for more Hubble time to confirm, and they gave us three tries,” said Keith Noll, Lucy project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and a co-discoverer of the satellite.

Image above: This diagram illustrates Lucy's orbital path. The spacecraft’s path (green) is shown in a frame of reference where Jupiter remains stationary, giving the trajectory its pretzel-like shape. After launch in October 2021, Lucy has two close Earth flybys before encountering its Trojan targets. In the L4 cloud Lucy will fly by (3548) Eurybates (white), (15094) Polymele (pink), (11351) Leucus (red), and (21900) Orus (red) from 2027-2028. After diving past Earth again Lucy will visit the L5 cloud and encounter the (617) Patroclus-Menoetius binary (pink) in 2033. As a bonus, in 2025 on the way to the L4, Lucy flies by a small Main Belt asteroid, (52246) Donaldjohanson (white), named for the discoverer of the Lucy fossil. After flying by the Patroclus-Menoetius binary in 2033, Lucy will continue cycling between the two Trojan clouds every six years. Image Credits: Southwest Research Institute.

The team was quick to make the first set of confirmation observations in December and early January. The possible satellite was hard to see and moving on an unknown orbit around the much brighter Eurybates. There was no guarantee that it would be visible in the new images. “In the first two observations in December we didn’t see anything, so we began to think we might be unlucky. But on the third orbit, there it was,” said Noll.

The team is working with Hubble schedulers to decide when to make the next observations after Eurybates becomes observable again. Due to the orbits of Earth and Eurybates, and because Hubble cannot be pointed toward the Sun, further observations are not possible until June. In the meantime, the team is using current observation data to study the satellite’s orbit around the asteroid, which will help scientists determine the best times for observations.

While there is no impact to the spacecraft architecture or schedule, the project team is carefully planning how to safely examine the new satellite while ensuring the mission’s requirement to study Eurybates is fully met.

Trojan asteroids have been trapped on orbits associated with the stable Lagrange Points for billions of years due to the combined gravitational influences of the Sun and Jupiter. Lucy will explore the diversity of these ancient leftover building blocks of the giant planets and will open new insights into the origins of our planet and the solar system.

Animation above: During the course of its mission, Lucy will fly by six Jupiter Trojans. This time-lapsed animation shows the movements of the inner planets (Mercury, brown; Venus, white; Earth, blue; Mars, red), Jupiter (orange), and the two Trojan swarms (green) during the course of the Lucy mission. Animation Credits: Astronomical Institute of CAS/Petr Scheirich.

“There are only a handful of known Trojan asteroids with satellites, and the presence of a satellite is particularly interesting for Eurybates,” said Thomas Statler, Lucy Program Scientist at NASA Headquarters in Washington. “It’s the largest member of the only confirmed Trojan collisional family – roughly 100 asteroids all traceable to, and probably fragments from, the same collision.”

The opportunity to study a prospective collisional satellite at close range will help our fundamental understanding of collisions, which Statler says may be responsible for the formation of satellites in other small body populations.

Southwest Research Institute in Boulder, Colorado, is the principal investigator institution for Lucy. Goddard provides overall mission management, systems engineering, and safety and mission assurance. Lockheed Martin Space Systems in Denver is building the spacecraft.

Discovery Program class missions like Lucy are relatively low-cost, with development capped at approximately $450 million. They are managed for NASA’s Planetary Science Division by the Planetary Missions Program Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama. The missions are led by a principal investigator who assembles a team of scientists and engineers to design and conduct the mission to address key science questions about the solar system.

Related link:

Lagrange Points:

For more information about the Lucy mission, visit: or

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Tricia Talbert/Grey Hautaluoma/Alana Johnson/GSFC/Nancy Neal Jones.


Crew Working Life Science, Looks Ahead to Upcoming Spacewalks

ISS - Expedition 61 Mission patch.

January 9, 2020

Human research and space biology filled the lab schedule aboard the International Space Station today. The Expedition 61 crewmembers are also ramping up for a trio of spacewalks set to begin next week.

NASA Flight Engineer Jessica Meir and Commander Luca Parmitano of ESA (European Space Agency) started Thursday collecting their blood samples. The duo spun the samples in a centrifuge and stowed them in a science freezer for later analysis. The astronauts also joined cosmonaut Alexander Skvortsov for a series of eye checks throughout the day.

Image above: Astronaut Jessica Meir waves during a spacewalk with fellow astronaut Christina Koch (out of frame) on Oct. 18, 2019. Image Credit: NASA.

Skvortsov also partnered up with cosmonaut Oleg Skripochka for cardiac research. After some Russian lab maintenance work, the pair also filmed educational activities to promote spaceflight for audiences on Earth.

Parmitano later tested how living in microgravity influences an astronaut’s perception of time. At the end of the workday, the ESA commander serviced a research incubator located in the Unity module.

International Space Station (ISS). Animation Credits: NASA

Flight Engineer Andrew Morgan is setting up a mouse habitat in Japan’s Kibo laboratory module. The research facility is part of the Cell Biology Experiment Facility and enables the observation of rodents, which have a physiology similar to humans, in different gravity conditions.

Meir and fellow NASA astronaut Christina Koch are getting ready for two of three spacewalks planned for this month. The spacewalkers will work outside the station on Jan. 15 and 20 to replace older batteries with newer, more powerful batteries on the orbiting lab’s Port-6 truss structure. Morgan and Parmitano are targeting a third spacewalk on Jan. 25 to finish repairing the station’s cosmic particle detector, the Alpha Magnetic Spectrometer.

Related links:

Expedition 61:

Cardiac research:

Promote spaceflight:

Astronaut’s perception of time:

Mouse habitat:

Kibo laboratory module:

Cell Biology Experiment Facility:

Port-6 truss structure:

Alpha Magnetic Spectrometer (AMS):

Space Station Research and Technology:

International Space Station (ISS):

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards,

CASC - Long March-3B launches TJSW-5

CASC - China Aerospace Science and Technology Corporation logo.

Jan. 9, 2020

Long March-3B launches TJSW-5

A Long March-3B launch vehicle launched the Communication Technology Test Satellite 5 (TJSW-5) from the Xichang Satellite Launch Center, Sichuan Province, southwest China, on 7 January 2020, at 15:20 UTC (23:20 local time).

Long March-3B launches TJSW-5

According to official sources, the satellite has successfully entered the preset orbit. TJSW-5 (通信技术试验卫星五号) will be used in communication, radio, television and data transmission, as well as high-throughput technology test.

Communication Technology Test Satellite 5 or TJSW-5. (Illustration)

For more information about China Aerospace Science and Technology Corporation (CASC):

For more information about China National Space Administration (CNSA):

Images, Video, Text, Credits: CASC/CNSA/China Central Television (CCTV)/SciNews/ Aerospace/Roland Berga.


The Swiss space telescope passes its first tests

ESA - Cheops Mission logo.

Jan. 9, 2020

The Swiss satellite-observatory carried out a first important mission on Wednesday.
Satellite successfully placed.

Soyuz ST-A launches CSG-1, CHEOPS, OPS-SAT, EyeSat & ANGELS

The Swiss space telescope CHEOPS has been in orbit since December 18. The satellite observatory passed its first major tests on Wednesday morning. It will still take a few weeks before the first real photos are taken.

Shortly after the launch in December, those involved in the CHEOPS mission tested communication with the satellite that carries the space telescope. After a break during the holidays, commissioning started this week: activate and test all components before CHEOPS can start its scientific mission.

First Swiss mission

CHEOPS (short for CHaracterising ExOPlanet Satellite) is the first mission of the European Space Agency (ESA) under the direction of Switzerland. Its objectives are to study exoplanets by observing the stars around which they orbit.

CHaracterising ExOPlanet Satellite (CHEOPS)

On Wednesday morning, CHEOPS passed two important tests: for the first time, the control center near Madrid attempted to start the telescope's computer. The team also checked the functionality of the satellite's heating elements, which can be used to control the temperature of the telescope. The instrument should not become too cold.

"It couldn't be better"

Both tests went extremely well. "It couldn't be better," CHEOPS mission director Willy Benz of the University of Bern enthusiastically told the Keystone-ATS news agency.

CHEOPS orbits the earth at an altitude of about 700 kilometers in about an hour and a half - always exactly along the day-night border. At dawn and dusk, the scientific satellite flies over the control center near Madrid and is then in range for one to two tests at most.

CHEOPS description

The team wants to take a first photo Thursday morning, but completely black. The telescope cover remains closed for some time. "There is still a lot to do before opening the lid," said Willy Benz. The first image is to show if the CCD charge transfer device suitable for CHEOPS works.

Hundreds of black images will follow next week to calibrate the instrument. The objective is to subsequently remove the interference signals induced by the hardware via an image correction. The cover can only be opened once and cannot be closed.

Moment of Truth

The moment of truth should come on January 27, when the lid will be opened. In the evening, when CHEOPS passes again over the control center near Madrid, the first real image will be taken and transmitted to the ground control center.

Data processing will take place at the "Science Operations Center" at the University of Geneva, that is to say the center where observation planning, daily management of scientific operations and data analysis will be carried out.

Cheops observing in space

Today, it is estimated that there are at least as many planets as stars in the galaxy, or about 100 billion. CHEOPS will observe about 500 of them and thus compose "a family photo of the exoplanets".

CHEOPS was developed and assembled by the University of Bern in close collaboration with the University of Geneva. More than 4,000 exoplanets - orbiting a star other than the Sun - have been detected since the discovery of the first, 51 Pegasi b, 24 years ago by the 2019 Nobel Prize winners Michel Mayor and Didier Queloz of the University of Geneva.

Related article & link:

Liftoff for Cheops, ESA’s exoplanet mission


Images, Videos, Text, Credits: ATS/ESA/ARIANESPACE/SciNews/ Aerospace/Roland Berga.

Best regards,

mercredi 8 janvier 2020

Goldilocks Stars Are Best Places to Look for Life

NASA - Hubble Space Telescope 25 Years patch.

Jan. 8, 2020

In the search for life beyond Earth, astronomers look for planets in a star's "habitable zone" — sometimes nicknamed the "Goldilocks zone" — where temperatures are just right for liquid water to exist on a planet's surface to nurture life as we know it.

An emerging idea, bolstered by a three-decade-long set of stellar surveys, is that there are "Goldilocks stars" — not too hot, not too cool, and above all, not too violent to host life-friendly planets.

Because our Sun has nurtured life on Earth for nearly 4 billion years, conventional wisdom would suggest that stars like it would be prime candidates in the search for other potentially habitable worlds. In reality, stars slightly cooler and less luminous than our Sun, classified as K dwarfs, are the true "Goldilocks stars," said Edward Guinan of Villanova University, Villanova, Pennsylvania. "K-dwarf stars are in the 'sweet spot,' with properties intermediate between the rarer, more luminous, but shorter-lived solar-type stars (G stars) and the more numerous red dwarf stars (M stars). The K stars, especially the warmer ones, have the best of all worlds. If you are looking for planets with habitability, the abundance of K stars pump up your chances of finding life."

Image above: This infographic compares the characteristics of three classes of stars in our galaxy: Sunlike stars are classified as G stars; stars less massive and cooler than our Sun are K dwarfs; and even fainter and cooler stars are the reddish M dwarfs. The graphic compares the stars in terms of several important variables. The habitable zones, potentially capable of hosting life-bearing planets, are wider for hotter stars. The longevity for red dwarf M stars can exceed 100 billion years. K dwarf ages can range from 15 to 45 billion years. And, our Sun only lasts for 10 billion years. The relative amount of harmful radiation (to life as we know it) that stars emit can be 80 to 500 times more intense for M dwarfs relative to our Sun, but only 5 to 25 times more intense for the orange K dwarfs. Red dwarfs make up the bulk of the Milky Way's population, about 73%. Sunlike stars are merely 6% of the population, and K dwarfs are at 13%. When these four variables are balanced, the most suitable stars for potentially hosting advanced life forms are K dwarfs. Image Credits: NASA, ESA and Z. Levy (STScI).

For starters, there are three times as many K dwarfs in our galaxy as stars like our Sun. Roughly 1,000 K stars lie within 100 light-years of our Sun as prime candidates for exploration. These so-called orange dwarfs live from 15 billion to 45 billion years. By contrast, our Sun, now already halfway through its lifetime, lasts for only 10 billion years. Its comparatively rapid rate of stellar evolution will leave the Earth largely uninhabitable in just another 1 or 2 billion years. "Solar-type stars limit how long a planet's atmosphere can remain stable," Guinan said. That's because a billion or so years from now, Earth will orbit inside the hotter (inner) edge of the Sun's habitable zone, which moves outward as the Sun grows warmer and brighter. As a result, the Earth will be desiccated as it loses its present atmosphere and oceans. By an age of 9 billion years the Sun will have swelled up to become a red giant that could engulf the Earth.

Despite their small size, the even more abundant red dwarf stars, also known as M dwarf stars, have even longer lifetimes and appear to be hostile to life as we know it. Planets that are located in a red dwarf's comparatively narrow habitable zone, which is very close to the star, are exposed to extreme levels of X-ray and ultraviolet (UV) radiation, which can be up to hundreds of thousands of times more intense than what Earth receives from the Sun. A relentless fireworks show of flares and coronal mass ejections bombard planets with a dragon's breath of seething plasma and showers of penetrating high-energy particles. Red dwarf habitable-zone planets can be baked bone dry and have their atmospheres stripped away very early in their lives. This could likely prohibit the planets from evolving to be more hospitable a few billion years after red dwarf outbursts have subsided. "We're not so optimistic anymore about the chances of finding advanced life around many M stars," Guinan said.

The K dwarfs do not have intensely active magnetic fields that power strong X-ray and UV emissions and energetic outbursts, and therefore they shoot off flares much less frequently, based on Guinan's research. Accompanying planets would get about 1/100th as much deadly X-ray radiation as those orbiting the close-in habitable zones of magnetically active M stars.

In a program called the "GoldiloKs" Project, Guinan and his Villanova colleague Scott Engle, are working with undergraduate students to measure the age, rotation rate, and X-ray and far-ultraviolet radiation in a sampling of mostly cool G and K stars.They are using NASA's Hubble Space Telescope, Chandra X-ray Observatory and ESA's (the European Space Agency) XMM-Newton satellite for their observations. Hubble's sensitive ultraviolet-light observations of radiation from hydrogen were used to assess the radiation from a sample of about 20 orange dwarfs. "Hubble is the only telescope that can do this kind of observation," Guinan said.

Hubble Space Telescope (HST). Image Credits: NASA/STS-109

Guinan and Engle found that the levels of radiation were much more benign to any accompanying planets than those found around red dwarfs. K stars also have longer lifetimes and therefore slower migration of the habitable zone. Therefore, K dwarfs seem like the ideal place to go looking for life, and these stars would allow time for highly evolved life to develop on planets. Over the Sun's entire lifetime — 10 billion years — K stars only increase their brightness by about 10-15%, giving biological evolution a much longer timespan to evolve advanced life forms than on Earth.

Guinan and Engle looked at some of the more interesting K stars hosting planets, including Kepler-442, Tau Ceti and Epsilon Eridani. (The latter two were early targets of the late 1950s Project Ozma — the first attempt to detect radio transmissions from extraterrestrial civilizations.)

"Kepler-442 is noteworthy in that this star (spectral classification, K5) hosts what is considered one of the best Goldilocks planets, Kepler-442b, a rocky planet that is a little more than twice Earth's mass. So the Kepler-442 system is a Goldilocks planet hosted by a Goldilocks star!" said Guinan.

Over the last 30 years Guinan and Engle and their students have observed a variety of stellar types. Based on their studies, the researchers have determined relationships among stellar age, rotation rate, X-ray-UV emissions and flare activity. These data have been utilized to investigate the effects of high-energy radiation on planet atmospheres and possible life.

The results are being presented at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii:

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Related links:

Hubble Space Telescope:


Images (mentioned), Text, Credits: NASA/Rob Garner/GSFC/Claire Andreoli/Space Telescope Science Institute/Ray Villard/Villanova University/Edward Guinan.


Hubble Detects Smallest Known Dark Matter Clumps

NASA - Hubble Space Telescope patch.

Jan. 8, 2020

Using NASA/ESA Hubble Space Telescope and a new observing technique, astronomers have found that dark matter forms much smaller clumps than previously known. This result confirms one of the fundamental predictions of the widely accepted "cold dark matter" theory.

All galaxies, according to this theory, form and are embedded within clouds of dark matter. Dark matter itself consists of slow-moving, or “cold,” particles that come together to form structures ranging from hundreds of thousands of times the mass of the Milky Way galaxy to clumps no more massive than the heft of a commercial airplane. (In this context, "cold" refers to the particles' speed.)

The Hubble observation yields new insights into the nature of dark matter and how it behaves. "We made a very compelling observational test for the cold dark matter model and it passes with flying colors," said Tommaso Treu of the University of California, Los Angeles (UCLA), a member of the observing team.

Hubble Space Telescope (HST). Animation Credits: NASA/ESA

Dark matter is an invisible form of matter that makes up the bulk of the universe's mass and creates the scaffolding upon which galaxies are built. Although astronomers cannot see dark matter, they can detect its presence indirectly by measuring how its gravity affects stars and galaxies. Detecting the smallest dark matter formations by looking for embedded stars can be difficult or impossible, because they contain very few stars.

While dark matter concentrations have been detected around large- and medium-sized galaxies, much smaller clumps of dark matter have not been found until now. In the absence of observational evidence for such small-scale clumps, some researchers have developed alternative theories, including "warm dark matter." This idea suggests that dark matter particles are fast moving, zipping along too quickly to merge and form smaller concentrations. The new observations do not support this scenario, finding that dark matter is "colder" than it would have to be in the warm dark matter alternative theory.

"Dark matter is colder than we knew at smaller scales," said Anna Nierenberg of NASA's Jet Propulsion Laboratory in Pasadena, California, leader of the Hubble survey. "Astronomers have carried out other observational tests of dark matter theories before, but ours provides the strongest evidence yet for the presence of small clumps of cold dark matter. By combining the latest theoretical predictions, statistical tools and new Hubble observations, we now have a much more robust result than was previously possible."

Hunting for dark matter concentrations devoid of stars has proved challenging. The Hubble research team, however, used a technique in which they did not need to look for the gravitational influence of stars as tracers of dark matter. The team targeted eight powerful and distant cosmic "streetlights," called quasars (regions around active black holes that emit enormous amounts of light). The astronomers measured how the light emitted by oxygen and neon gas orbiting each of the quasars' black holes is warped by the gravity of a massive foreground galaxy, which is acting as a magnifying lens.

Image above: Each of these Hubble Space Telescope snapshots reveals four distorted images of a background quasar and its host galaxy surrounding the central core of a foreground massive galaxy. The gravity of the massive foreground galaxy is acting like a magnifying glass by warping the quasar’s light in an effect called gravitational lensing. Quasars are extremely distant cosmic streetlights produced by active black holes. Such quadruple images of quasars are rare because of the nearly exact alignment needed between the foreground galaxy and background quasar. Astronomers used the gravitational lensing effect to detect the smallest clumps of dark matter ever found. The clumps are located along the telescope's line of sight to the quasars, as well as in and around the foreground lensing galaxies. The presence of the dark matter concentrations alters the apparent brightness and position of each distorted quasar image. Astronomers compared these measurements with predictions of how the quasar images would look without the influence of the dark matter clumps. The researchers used these measurements to calculate the masses of the tiny dark matter concentrations. Hubble's Wide Field Camera 3 captured the near-infrared light from each quasar and dispersed it into its component colors for study with spectroscopy. The images were taken between 2015 and 2018. Image Credits: NASA, ESA, A. Nierenberg (JPL) and T. Treu (UCLA).

Using this method, the team uncovered dark matter clumps along the telescope's line of sight to the quasars, as well as in and around the intervening lensing galaxies. The dark matter concentrations detected by Hubble are 1/10,000th to 1/100,000th times the mass of the Milky Way's dark matter halo. Many of these tiny groupings most likely do not contain even small galaxies, and therefore would have been impossible to detect by the traditional method of looking for embedded stars.

The eight quasars and galaxies were aligned so precisely that the warping effect, called gravitational lensing, produced four distorted images of each quasar. The effect is like looking at a funhouse mirror. Such quadruple images of quasars are rare because of the nearly exact alignment needed between the foreground galaxy and background quasar. However, the researchers needed the multiple images to conduct a more detailed analysis.

The presence of the dark matter clumps alters the apparent brightness and position of each distorted quasar image. Astronomers compared these measurements with predictions of how the quasar images would look without the influence of the dark matter. The researchers used the measurements to calculate the masses of the tiny dark matter concentrations. To analyze the data, the researchers also developed elaborate computing programs and intensive reconstruction techniques.

"Imagine that each one of these eight galaxies is a giant magnifying glass," explained team member Daniel Gilman of UCLA. "Small dark matter clumps act as small cracks on the magnifying glass, altering the brightness and position of the four quasar images compared to what you would expect to see if the glass were smooth."

Image above: This graphic illustrates how a faraway quasar's light is altered by a massive foreground galaxy and by tiny dark matter clumps along the light path. The galaxy's powerful gravity warps and magnifies the quasar's light, producing four distorted images of the quasar.The dark matter clumps reside along the Hubble Space Telescope's line of sight to the quasar, as well as within and around the foreground galaxy. The presence of the dark matter clumps alters the apparent brightness and position of each distorted quasar image by warping and slightly bending the light as it travels from the distant quasar to Earth, as represented by the wiggly lines in the graphic. Astronomers compared these measurements with predictions of how the quasar images would look without the influence of the dark matter clumps. The researchers used these measurements to calculate the masses of the tiny dark matter concentrations. Quadruple images of a quasar are rare because the background quasar and foreground galaxy require an almost perfect alignment. Image Credits: NASA, ESA and D. Player (STScI).

The researchers used Hubble’s Wide Field Camera 3 to capture the near-infrared light from each quasar and disperse it into its component colors for study with spectroscopy. Unique emissions from the background quasars are best seen in infrared light. "Hubble's observations from space allow us to make these measurements in galaxy systems that would not be accessible with the lower resolution of ground-based telescopes—and Earth's atmosphere is opaque to the infrared light we needed to observe," explained team member Simon Birrer of UCLA.

Treu added: "It's incredible that after nearly 30 years of operation, Hubble is enabling cutting-edge views into fundamental physics and the nature of the universe that we didn't even dream of when the telescope was launched."

The gravitational lenses were discovered by sifting through ground-based surveys such as the Sloan Digital Sky Survey and Dark Energy Survey, which provide the most detailed three-dimensional maps of the universe ever made. The quasars are located roughly 10 billion light-years from Earth; the foreground galaxies, about 2 billion light-years.

The number of small structures detected in the study offers more clues about dark matter's nature. "The particle properties of dark matter affect how many clumps form," Nierenberg explained. "That means you can learn about the particle physics of dark matter by counting the number of small clumps."

However, the type of particle that makes up dark matter is still a mystery. "At present, there's no direct evidence in the lab that dark matter particles exist," Birrer said. "Particle physicists would not even talk about dark matter if the cosmologists didn’t say it's there, based on observations of its effects. When we cosmologists talk about dark matter, we're asking 'how does it govern the appearance of the universe, and on what scales?'"

Astronomers will be able to conduct follow-up studies of dark matter using future NASA space telescopes such as the James Webb Space Telescope and the Wide Field Infrared Survey Telescope (WFIRST), both infrared observatories. Webb will be capable of efficiently obtaining these measurements for all known quadruply lensed quasars. WFIRST's sharpness and large field of view will help astronomers make observations of the entire region of space affected by the immense gravitational field of massive galaxies and galaxy clusters. This will help researchers uncover many more of these rare systems.

The team will present its results at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii:

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Related links:

Hubble Space Telescope:

Dark Energy and Dark Matter:

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Rob Garner/GFSC/Claire Andreoli/JPL/Anna Nierenberg/University of California/Tommaso Treu/Daniel Gilman.

Best regards,

Cosmic Magnifying Glasses Yield Independent Measure of Universe's Expansion

NASA - Hubble Space Telescope patch.

Jan. 8, 2020

A team of astronomers using NASA/ESA Hubble Space Telescope has measured the universe's expansion rate using a technique that is completely independent of any previous method.

Knowing the precise value for how fast the universe expands is important for determining the age, size and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

The researchers' result further strengthens a troubling discrepancy between the expansion rate, called the Hubble constant, calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed.

This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects. This latest study did not rely on the traditional "cosmic distance ladder" technique to measure accurate distances to galaxies by using various types of stars as "milepost markers." Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universe's expansion rate.

The astronomy team that made the new Hubble constant measurements is dubbed H0LiCOW (H0 Lenses in COSMOGRAIL's Wellspring). COSMOGRAIL is the acronym for Cosmological Monitoring of Gravitational Lenses, a large international project whose goal is monitoring gravitational lenses. "Wellspring" refers to the abundant supply of quasar lensing systems.

The research team derived the H0LiCOW value for the Hubble constant through observing and analysis techniques that have been greatly refined over the past two decades.

H0LiCOW and other recent measurements suggest a faster expansion rate in the local universe than was expected based on observations by the European Space Agency's Planck satellite of how the cosmos behaved more than 13 billion years ago.

The gulf between the two values has important implications for understanding the universe's underlying physical parameters and may require new physics to account for the mismatch.

"If these results do not agree, it may be a hint that we do not yet fully understand how matter and energy evolved over time, particularly at early times," said H0LiCOW team leader Sherry Suyu of the Max Planck Institute for Astrophysics in Germany, the Technical University of Munich, and the Academia Sinica Institute of Astronomy and Astrophysics in Taipei, Taiwan.

How They Did It

The H0LiCOW team used Hubble to observe the light from six faraway quasars, the brilliant searchlights from gas orbiting supermassive black holes at the centers of galaxies. Quasars are ideal background objects for many reasons; for example, they are bright, extremely distant and scattered all over the sky. The telescope observed how the light from each quasar was multiplied into four images by the gravity of a massive foreground galaxy. The galaxies studied are 3 billion to 6.5 billion light-years away. The quasars' average distance is 5.5 billion light-years from Earth.

Image above: Each of these Hubble Space Telescope snapshots reveals four distorted images of a background quasar surrounding the central core of a foreground massive galaxy. The multiple quasar images were produced by the gravity of the foreground galaxy, which is acting like a magnifying glass by warping the quasar’s light in an effect called gravitational lensing. Quasars are extremely distant cosmic streetlights produced by active black holes. The Hubble images were taken between 2003 and 2004 with the Advanced Camera for Surveys. Image Credits: NASA, ESA, S.H. Suyu (Max Planck Institute for Astrophysics, Technical University of Munich, and Academia Sinica Institute of Astronomy and Astrophysics) and K.C. Wong (University of Tokyo’s Kavli Institute for the Physics and Mathematics of the Universe).

The light rays from each lensed quasar image take a slightly different path through space to reach Earth. The pathway's length depends on the amount of matter that is distorting space along the line of sight to the quasar. To trace each pathway, the astronomers monitor the flickering of the quasar's light as its black hole gobbles up material. When the light flickers, each lensed image brightens at a different time.

This flickering sequence allows researchers to measure the time delays between each image as the lensed light travels along its path to Earth. To fully understand these delays, the team first used Hubble to make accurate maps of the distribution of matter in each lensing galaxy. Astronomers could then reliably deduce the distances from the galaxy to the quasar, and from Earth to the galaxy and to the background quasar. By comparing these distance values, the researchers measured the universe's expansion rate.

"The length of each time delay indicates how fast the universe is expanding," said team member Kenneth Wong of the University of Tokyo's Kavli Institute for the Physics and Mathematics of the Universe, lead author of the H0LiCOW collaboration's most recent paper. "If the time delays are shorter, then the universe is expanding at a faster rate. If they are longer, then the expansion rate is slower."

The time-delay process is analogous to four trains leaving the same station at exactly the same time and traveling at the same speed to reach the same destination. However, each of the trains arrives at the destination at a different time. That’s because each train takes a different route, and the distance for each route is not the same. Some trains travel over hills. Others go through valleys, and still others chug around mountains. From the varied arrival times, one can infer that each train traveled a different distance to reach the same stop. Similarly, the quasar flickering pattern does not appear at the same time because some of the light is delayed by traveling around bends created by the gravity of dense matter in the intervening galaxy.

How it Compares

The researchers calculated a Hubble constant value of 73 kilometers per second per megaparsec (with 2.4% uncertainty). This means that for every additional 3.3 million light-years away a galaxy is from Earth, it appears to be moving 73 kilometers per second faster, because of the universe's expansion.

Hubble Space Telescope (HST). Image Credit: NASA

The team's measurement also is close to the Hubble constant value of 74 calculated by the Supernova H0 for the Equation of State (SH0ES) team, which used the cosmic distance ladder technique. The SH0ES measurement is based on gauging the distances to galaxies near and far from Earth by using Cepheid variable stars and supernovas as measuring sticks to the galaxies.

The SH0ES and H0LiCOW values significantly differ from the Planck number of 67, strengthening the tension between Hubble constant measurements of the modern universe and the predicted value based on observations of the early universe.

"One of the challenges we overcame was having dedicated monitoring programs through COSMOGRAIL to get the time delays for several of these quasar lensing systems," said Frédéric Courbin of the Ecole Polytechnique Fédérale de Lausanne, leader of the COSMOGRAIL project.

Suyu added: "At the same time, new mass modeling techniques were developed to measure a galaxy's matter distribution, including models we designed to make use of the high-resolution Hubble imaging. The images enabled us to reconstruct, for example, the quasars' host galaxies. These images, along with additional wider-field images taken from ground-based telescopes, also allow us to characterize the environment of the lens system, which affects the bending of light rays. The new mass modeling techniques, in combination with the time delays, help us to measure precise distances to the galaxies."

Begun in 2012, the H0LiCOW team now has Hubble images and time-delay information for 10 lensed quasars and intervening lensing galaxies. The team will continue to search for and follow up on new lensed quasars in collaboration with researchers from two new programs. One program, called STRIDES (STRong-lensing Insights into Dark Energy Survey), is searching for new lensed quasar systems. The second, called SHARP (Strong-lensing at High Angular Resolution Program), uses adaptive optics with the W.M. Keck telescopes to image the lensed systems. The team's goal is to observe 30 more lensed quasar systems to reduce their 2.4% percent uncertainty to 1%.

NASA's upcoming James Webb Space Telescope, expected to launch in 2021, may help them achieve their goal of 1% uncertainty much faster through Webb's ability to map the velocities of stars in a lensing galaxy, which will allow astronomers to develop more precise models of the galaxy's distribution of dark matter.

The H0LiCOW team's work also paves the way for studying hundreds of lensed quasars that astronomers are discovering through surveys such as the Dark Energy Survey and PanSTARRS (Panoramic Survey Telescope and Rapid Response System), and the upcoming National Science Foundation's Large Synoptic Survey Telescope, which is expected to uncover thousands of additional sources.

In addition, NASA's Wide Field Infrared Survey Telescope (WFIRST) will help astronomers address the disagreement in the Hubble constant value by tracing the expansion history of the universe. The mission will also use multiple techniques, such as sampling thousands of supernovae and other objects at various distances, to help determine whether the discrepancy is a result of measurement errors, observational technique, or whether astronomers need to adjust the theory from which they derive their predictions.

The team will present its results at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii:

The Hubble Space Telescope is a project of international cooperation between the European Space Agency (ESA) and NASA. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Related Links:

Probing the Hubble Constant with NASA's WFIRST:

Hubble Space Telescope:

Images (mentioned), Text, Credits: NASA/Rob Garner/GSFC/Claire Andreoli/Space Telescope Science Institute/Donna Weaver/Ray Villard/Max Planck Institute for Astrophysics/Sherry Suyu.


What Happens When Planets Collide

NASA & DLR - SOFIA Mission patch.

Jan. 8, 2020

This artist’s concept illustrates a catastrophic collision between two rocky exoplanets in the planetary system BD +20 307, turning both into dusty debris. Ten years ago, scientists speculated that the warm dust in this system was a result of a planet-to-planet collision. Now, NASA's SOFIA mission found even more warm dust, further supporting that two rocky exoplanets collided. This helps build a more complete picture of our own solar system’s history. Such a collision could be similar to the type of catastrophic event that ultimately created our Moon.



Image, Text, Credits: NASA/Yvette Smith/SOFIA/Lynette Cook.


Spacewalk Preps Underway Amidst Space Research

ISS - Expedition 61 Mission patch.

January 8, 2020

The Expedition 61 crew is gearing up for the first three spacewalks of 2020 set for this month. Meanwhile, the International Space Station is bustling with an array of microgravity research activities today.

NASA astronauts Jessica Meir and Christina Koch will conduct the first two spacewalks scheduled for Jan. 15 and Jan. 20. The duo will finish replacing older nickel-hydrogen batteries with new lithium-ion batteries on the station’s Port-6 truss structure. They spent Wednesday reviewing spacewalk procedures and inspecting spacesuit tethers.

Image above: The Expedition 61 crew gathers together for a meal. Clockwise from top left are, Christina Koch, Oleg Skripochka, Luca Parmitano, Alexander Skvortsov, Jessica Meir and Andrew Morgan. Image Credit: NASA.

The next spacewalk would be Jan. 25 following the successful battery replacements. NASA astronaut Andrew Morgan and Commander Luca Parmitano of ESA (European Space Agency) will finish the repair work they started in November on the station’s cosmic particle detector, the Alpha Magnetic Spectrometer.

In the midst of the spacewalk preparations, the lab residents kept up the ongoing space science to improve life for humans on and off Earth.

Image above: NASA astronaut Jessica Meir takes an out-of-this-world "space-selfie" with her spacesuit helmet visor down reflecting her camera and International Space Station hardware. She and fellow NASA astronaut Christina Koch (out of frame) ventured into the vacuum of space for seven hours and 17 minutes to swap a failed battery charge-discharge unit (BCDU) with a spare during the first all-woman spacewalk. Image Credit: NASA.

Morgan began the day installing botany research gear inside Japan’s Cell Biology Experiment Facility before transferring resupply racks to the Cygnus space freighter. Parmitano conducted a vision test then cleaned up Rodent Research hardware that housed mice that were returned to Earth aboard the SpaceX Dragon cargo craft.

Cosmonauts Alexander Skvortsov and Oleg Skripochka split their time on Russian science and maintenance tasks. The duo partnered together for a study exploring piloting methods under a variety of gravity conditions. Skvortsov then measured the station’s radiation environment as Skripochka replaced fuel bottles for combustion research.

Related articles:

Dragon Splashes Down in Pacific Returning Science and Cargo

Dragon Released from Station Carrying Science for Earth-Analysis

Related links:

Expedition 61:

First three spacewalks of 2020:

Alpha Magnetic Spectrometer (AMS):

Cell Biology Experiment Facility:

Rodent Research:

Piloting methods:

Rradiation environment:

Combustion research:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards,

SOFIA Reveals How the Swan Nebula Hatched

NASA & DLR - SOFIA Mission patch.

January 8, 2020

Image above: In this composite image of the Omega, or Swan, Nebula, SOFIA detected the blue areas near the center and the green areas. The white star field was detected by Spitzer. SOFIA's view reveals evidence that parts of the nebula formed separately to create the swan-like shape seen today.Image Credits: NASA/SOFIA/Lim, De Buizer, & Radomski et al.; ESA/Herschel; NASA/JPL-Caltech.

One of the brightest and most massive star-forming regions in our galaxy, the Omega, or Swan, Nebula, came to resemble the shape resembling a swan's neck we see today only relatively recently. New observations reveal that its regions formed separately over multiple eras of star birth. The new image from the Stratospheric Observatory for Infrared Astronomy, or SOFIA, is helping scientists chronicle the history and evolution of this well-studied nebula.

"The present-day nebula holds the secrets that reveal its past; we just need to be able to uncover them," said Wanggi Lim, a Universities Space Research Association scientist at the SOFIA Science Center at NASA's Ames Research Center in California's Silicon Valley. "SOFIA lets us do this, so we can understand why the nebula looks the way it does today."

Uncovering the nebula's secrets is no simple task. It's located more than 5,000 light-years away in the constellation Sagittarius. Its center is filled with more than 100 of the galaxy's most massive young stars. These stars may be many times the size of our Sun, but the youngest generations are forming deep in cocoons of dust and gas, where they are very difficult to see, even with space telescopes. Because the central region glows very brightly, the detectors on space telescopes were saturated at the wavelengths SOFIA studied, similar to an overexposed photo.

SOFIA's infrared camera called FORCAST, the Faint Object Infrared Camera for the SOFIA Telescope, however, can pierce through these cocoons.

The new view reveals nine protostars, areas where the nebula's clouds are collapsing and creating the first step in the birth of stars, that had not been seen before. Additionally, the team calculated the ages of the nebula's different regions. They found that portions of the swan-like shape were not all created at the same time, but took shape over multiple eras of star formation.

The central region is the oldest, most evolved and likely formed first. Next, the northern area formed, while the southern region is the youngest. Even though the northern area is older than the southern region, the radiation and stellar winds from previous generations of stars has disturbed the material there, preventing it from collapsing to form the next generation.

"This is the most detailed view of the nebula we have ever had at these wavelengths," said Jim De Buizer, a senior scientist also at the SOFIA Science Center. "It's the first time we can see some of its youngest, massive stars and start to truly understand how it evolved into the iconic nebula we see today."

Massive stars, like those in the Swan Nebula, release so much energy that they can change the evolution of entire galaxies. But less than 1% of all stars are this enormous, so astronomers know very little about them. Previous observations of this nebula with space telescopes studied different wavelengths of infrared light, which did not reveal the details SOFIA detected.

SOFIA's image shows gas in blue as it's heated by massive stars located near the center, and dust in green that is warmed both by existing massive stars and nearby newborn stars. The newly-detected protostars are located primarily in the southern areas. The red areas near the edge represent cold dust that was detected by the Herschel Space Telescope, while the white star field was detected by the Spitzer Space Telescope.

The Spitzer Space Telescope will be decommissioned on Jan. 30, 2020, after operating for more than 16 years. SOFIA continues exploring the infrared universe, building on Spitzer's legacy. SOFIA studies wavelengths of mid- and far-infrared light with high resolution that are not accessible to other telescopes, helping scientists understand star and planet formation, the role magnetic fields play in shaping our universe, and the chemical evolution of galaxies.

SOFIA, the Stratospheric Observatory for Infrared Astronomy, is a Boeing 747SP jetliner modified to carry a 106-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center (DLR). NASA's Ames Research Center in California's Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is maintained and operated from NASA's Armstrong Flight Research Center Building 703, in Palmdale, California.

Boeing 747SP SOFIA telescope bay door opening. Animation Credit: NASA

JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena, California. Space operations are based at Lockheed Martin Space in Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

Herschel is a European Space Agency mission, with science instruments provided by consortia of European institutes and with important participation by NASA. While the observatory stopped making science observations in April 2013, after running out of liquid coolant as expected, scientists continue to analyze its data. NASA's Herschel Project Office is based at NASA's Jet Propulsion Laboratory in Pasadena. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of IPAC, supports the U.S. astronomical community. Caltech manages JPL for NASA.

Stratospheric Observatory for Infrared Astronomy (SOFIA):

Spitzer Space Telescope:

Herschel Space Observatory:

Image (mentioned),  Animation (mentioned), Text, Credits: NASA/JPL/Calla Cofield/USRA/SOFIA, written by Kassandra Bell.